Abstract Anemia, characterized by low blood hemoglobin (Hgb) levels, is the world?s most common blood disorder, afflicting nearly two billion people, especially young children, the elderly, and women of childbearing age. Due to numerous etiologies, anemia can also be chronic and potentially life-threatening. Currently, the gold-standard diagnostic test for anemia is the complete blood count (CBC), which requires a patient visit to a clinic/hospital or commercial lab as well as trained phlebotomists/technicians. However, access to this test is cost-prohibitive in low resource settings (LRS), where unfortunately, anemia is most prevalent worldwide with the highest rates of anemia-associated mortality. Due to the inconvenience, invasiveness, lack of accessibility, and cost associated with CBCs, point-of-care (POC) Hgb diagnostics have been developed, but current systems all suffer from high-cost (handheld Hgb meters cost USD $30-$1000), inaccuracy, the need for blood sampling, or reagent instability in the potentially harsh environments of LRS. Currently, no non-invasive, inexpensive, easily accessible (i.e. external device free and widely available) POC anemia diagnostic exists that accurately measures a patient?s Hgb levels, especially as a patient self-test. To address these critical challenges, Sanguina, LLC has developed a novel, non-invasive smartphone app that measures blood Hgb levels using only smartphone photos and the smartphone?s native hardware and has recently published the initial presentation and clinical assessment of this novel technology (Mannino et al, Nature Communications). Interestingly, whereas medical infrastructure in LRS is lacking, mobile phone infrastructure is comparatively advanced and significant parts of the population in LRS have smartphone access, enabling smartphone-based solutions to be ideal diagnostics in global health. As conducting a true clinical validation study in global health settings requires access to gold standard CBC Hgb levels, which is logistically difficult to implement in LRS, we will conduct our study on local refugee populations recently emigrated from LRS as a surrogate global health population. Anemia affects 40% of these refugees and as such, necessitates intake screening and monitoring through anemia control programs. This population represents an ideal study population to locally evaluate the potential of our app to effectively screen anemia in LRS. In this Phase I SBIR, we aim to: 1) evaluate the accuracy of our low-cost, non-invasive smartphone Hgb level measurement app against Hgb levels obtained with routinely used POC tools in the refugee population at the Dekalb County Board of Health, .2) Assess the usability of the app in the hands of clinicians and patients, and 3). Develop a consumer-facing, user-friendly app based on clinician and patient feedback. Overall, the successful completion of this proposal will result in a truly paradigm-shifting and cost-effective tool in the management of anemia worldwide and especially in global health settings.